It is known that synchronous generators are used for the conversion of mechanical into electrical energy. Dependent on the frequency of rotation and the excitation of the rotor winding of the synchronous generator a voltage with a corresponding height and frequency will be generated. Such a variable power source might be required as auxiliary power supply in a power plant for example.
The rated power of such variable auxiliary power supplies with rotating generators might be around 12 MVA/4 MW for example wherein the rated output voltage might amount 10 kV. In the case that such a generator is not ready for operation during a certain time, for example due to scheduled maintenance or a breakdown, a prompt replacement is required in order to supply the respective loads with electric energy of the desired voltage and frequency anyhow.
But also for purposes of testing of electrical equipment such as high power transformers, for example with a rated power of 100 MW and above, a variable power source might be required. For the test of such large components it is more common to transport the test equipment to the component to be tested instead of transporting the component to the test equipment.
Disadvantageously within the state of the art is that the transport of a variable power source with rotating generator is rather difficult and time consuming due to its high weight and size. In case of a temporary installation for test purposes it has also to be ensured, that a suitable groundwork is available at the installation site of the generator.